Esters-buliding-blocks

Eco-sustainable systems based on poly(lactic acid), diatomite and coffee grounds extract for food packaging was written by Cacciotti, Ilaria;Mori, Stefano;Cherubini, Valeria;Nanni, Francesca. And the article was included in International Journal of Biological Macromolecules in 2018.Electric Literature of C20H40O2 The following contents are mentioned in the article:

In the food packaging sector many efforts have been (and are) devoted to the development of new materials in order to reply to an urgent market demand for green and eco-sustainable products. Particularly a lot of attention is currently devoted both to the use of compostable and biobased polymers as innovative and promising alternative to the currently used petrochem. derived polymers, and to the re-use of waste materials coming from agriculture and food industry. In this work, multifunctional eco-sustainable systems, based on poly(lactic acid) (PLA) as biopolymeric matrix, diatomaceous earth as reinforcing filler and spent coffee grounds extract as oxygen scavenger, were produced for the first time, in order to provide a simultaneous improvement of mech. and gas barrier properties. The influence of the diatomite and the spent coffee grounds extract on the microstructural, mech. and oxygen barrier properties of the produced films was deeply investigated by means of X-Ray diffraction (XRD), IR spectroscopy (FT-IR, ATR), SEM (SEM), uniaxial tensile tests, O₂ permeabilimetry measurements. An improvement of both mech. and oxygen barrier properties was recorded for systems characterised by the co-presence of diatomite and coffee grounds extract, suggesting a possible synergic effect of the two additives. This study involved multiple reactions and reactants, such as Methyl nonadecanoate (cas: 1731-94-8Electric Literature of C20H40O2).

Methyl nonadecanoate (cas: 1731-94-8) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. Liquid esters of low volatility serve as softening agents for resins and plastics. Esters also include many industrially important polymers. Polymethyl methacrylate is a glass substitute sold under the names Lucite and Plexiglas; polyethylene terephthalate is used as a film (Mylar) and as textile fibres sold as Terylene, Fortrel, and Dacron.Electric Literature of C20H40O2

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Selective detection of phospholipids using molecularly imprinted fluorescent sensory core-shell particles was written by Li, Qianjin;Shinde, Sudhirkumar;Grasso, Giuliana;Caroli, Antonio;Abouhany, Rahma;Lanzillotta, Michele;Pan, Guoqing;Wan, Wei;Rurack, Knut;Sellergren, Boerje. And the article was included in Scientific Reports in 2020.Safety of (2R,9Z)-1-(((2-Aminoethoxy)(hydroxy)phosphoryl)oxy)-3-(palmitoyloxy)propan-2-yl oleate The following contents are mentioned in the article:

Sphingosine-1-phosphate (S1P) is a bioactive sphingo-lipid with a broad range of activities coupled to its role in G-protein coupled receptor signalling. Monitoring of both intra and extra cellular levels of this lipid is challenging due to its low abundance and lack of robust affinity assays or sensors. We here report on fluorescent sensory core-shell molecularly imprinted polymer (MIP) particles responsive to near physiol. relevant levels of S1P and the S1P receptor modulator fingolimod phosphate (FP) in spiked human serum samples. Imprinting was achieved using the tetrabutylammonium (TBA) salt of FP or phosphatidic acid (DPPA·Na) as templates in combination with a polymerizable nitrobenzoxadiazole (NBD)-urea monomer with the dual role of capturing the phospho-anion and signalling its presence. The monomers were grafted from ca 300 nm RAFT-modified silica core particles using ethyleneglycol dimethacrylate (EGDMA) as crosslinker resulting in 10-20 nm thick shells displaying selective fluorescence response to the targeted lipids S1P and DPPA in aqueous buffered media. Potential use of the sensory particles for monitoring S1P in serum was demonstrated on spiked serum samples, proving a linear range of 18-60μM and a detection limit of 5.6μM, a value in the same range as the plasma concentration of the biomarker. This study involved multiple reactions and reactants, such as (2R,9Z)-1-(((2-Aminoethoxy)(hydroxy)phosphoryl)oxy)-3-(palmitoyloxy)propan-2-yl oleate (cas: 26662-94-2Safety of (2R,9Z)-1-(((2-Aminoethoxy)(hydroxy)phosphoryl)oxy)-3-(palmitoyloxy)propan-2-yl oleate).

(2R,9Z)-1-(((2-Aminoethoxy)(hydroxy)phosphoryl)oxy)-3-(palmitoyloxy)propan-2-yl oleate (cas: 26662-94-2) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Liquid esters of low volatility serve as softening agents for resins and plastics. Esters also include many industrially important polymers. Polymethyl methacrylate is a glass substitute sold under the names Lucite and Plexiglas; polyethylene terephthalate is used as a film (Mylar) and as textile fibres sold as Terylene, Fortrel, and Dacron.Safety of (2R,9Z)-1-(((2-Aminoethoxy)(hydroxy)phosphoryl)oxy)-3-(palmitoyloxy)propan-2-yl oleate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Biomimetic nanoparticles deliver mRNAs encoding costimulatory receptors and enhance T cell mediated cancer immunotherapy was written by Li, Wenqing;Zhang, Xinfu;Zhang, Chengxiang;Yan, Jingyue;Hou, Xucheng;Du, Shi;Zeng, Chunxi;Zhao, Weiyu;Deng, Binbin;McComb, David W.;Zhang, Yuebao;Kang, Diana D.;Li, Junan;Carson, William E. III;Dong, Yizhou. And the article was included in Nature Communications in 2021.Reference of 604-69-3 The following contents are mentioned in the article:

Abstract: Antibodies targeting costimulatory receptors of T cells have been developed for the activation of T cell immunity in cancer immunotherapy. However, costimulatory mol. expression is often lacking in tumor-infiltrating immune cells, which can impede antibody-mediated immunotherapy. Here, we hypothesize that delivery of costimulatory receptor mRNA to tumor-infiltrating T cells will enhance the antitumor effects of antibodies. We first design a library of biomimetic nanoparticles and find that phospholipid nanoparticles (PL1) effectively deliver costimulatory receptor mRNA (CD137 or OX40) to T cells. Then, we demonstrate that the combination of PL1-OX40 mRNA and anti-OX40 antibody exhibits significantly improved antitumor activity compared to anti-OX40 antibody alone in multiple tumor models. This treatment regimen results in a 60% complete response rate in the A20 tumor model, with these mice being resistant to rechallenge by A20 tumor cells. Addnl., the combination of PL1-OX40 mRNA and anti-OX40 antibody significantly boosts the antitumor immune response to anti-PD-1 + anti-CTLA-4 antibodies in the B16F10 tumor model. This study supports the concept of delivering mRNA encoding costimulatory receptors in combination with the corresponding agonistic antibody as a strategy to enhance cancer immunotherapy. This study involved multiple reactions and reactants, such as (2S,3R,4S,5R,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 604-69-3Reference of 604-69-3).

(2S,3R,4S,5R,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 604-69-3) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Esters are more polar than ethers but less polar than alcohols. They participate in hydrogen bonds as hydrogen-bond acceptors, but cannot act as hydrogen-bond donors, unlike their parent alcohols. This ability to participate in hydrogen bonding confers some water-solubility.Reference of 604-69-3

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Comparison of volatile compounds in two brandies using HS-SPME coupled with GC-O, GC-MS and sensory evaluation was written by Zhao, Y. P.;Wang, L.;Li, J. M.;Pei, G. R.;Liu, Q. S.. And the article was included in South African Journal of Enology and Viticulture in 2011.COA of Formula: C7H14O3 The following contents are mentioned in the article:

The aim of this study was to compare the volatile compounds between Changyu XO and Hennessy XO. Sensory evaluation was performed by a panel of tasters. Qual. and semi-quant. anal. was achieved by headspace solid phase micro-extraction (HS-SPME), coupled with gas chromatog.-mass spectrometry (GC-MS) and gas chromatog.-olfactometry (GC-O). A total of 160 volatile compounds were identified in the two brands of brandy. Of these, 118 compounds were common to both Changyu XO and Hennessy XO; 18 compounds were specific to Changyu XO and 24 were specific to Hennessy XO. A total of 85 aroma compounds responsible for brandy flavor were identified by GC-O, of which 68 were common to both brands, while seven and ten were specific to Changyu XO and Hennessy XO, resp. The study provided detailed information about the compounds responsible for the characteristic flavor of specific brandies. According to statistical anal., significant differences were recorded between Changyu XO and Hennessy XO. Most volatile compounds in Changyu XO occurred at lower concentrations than those in Hennessy XO. Based on sensory evaluation anal., the floral, alc. and rancid aroma descriptors achieved higher scores in Changyu XO and Hennessy XO, while the lime aroma seemed specific to Hennessy XO. Herb and almond aromas were specific to Changyu XO. This study involved multiple reactions and reactants, such as Ethyl 3-ethoxypropanoate (cas: 763-69-9COA of Formula: C7H14O3).

Ethyl 3-ethoxypropanoate (cas: 763-69-9) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Esters are more polar than ethers but less polar than alcohols. They participate in hydrogen bonds as hydrogen-bond acceptors, but cannot act as hydrogen-bond donors, unlike their parent alcohols. This ability to participate in hydrogen bonding confers some water-solubility.COA of Formula: C7H14O3

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Full atom-efficiency transformation of wasted polycarbonates into epoxy thermosets and the catalyst-free degradation of the thermosets for environmental sustainability was written by Shao, Shih Wei;Chen, Chien Han;Chan, Jian Ren;Juang, Tzong Yuan;Abu-Omar, Mahdi M.;Lin, Ching Hsuan. And the article was included in Green Chemistry in 2020.Formula: C13H10O3 The following contents are mentioned in the article:

We report two sustainable features in this work. The first feature is that we successfully applied wasted polycarbonate (WPC) as an epoxy curing agent for epoxy resins to prepare WPC-cured epoxy thermosets. The curing of WPC and epoxy is based on the reaction of a carbonate and an epoxide, which is proven by a model reaction of di-Ph carbonate (DPC) and glycidyl Ph ether (GPE) in the presence of a catalytic amount of 4-dimethylaminopyridine (DMAP). The WPC-cured epoxy thermosets show comparable thermal properties to com.-based, phenol novolac (PN)-cured epoxy thermosets. Interestingly, the films of WPC-cured epoxy thermosets are foldable, while those of PN-cured epoxy thermosets are brittle, demonstrating the advantage of using WPC as a curing agent over PN. Since the WPC was used directly without any digestion or pyrolysis process, the at. efficiency is 100%, making this WPC recycling strategy economically attractive. The second feature is that we successfully degraded the WPC-cured epoxy thermosets to phenoxy resins through a catalyst-free aminolysis process, i.e., the products based on the WPC-cured epoxy thermosets are degradable when their lifespans are expired. The transformation of WPC into epoxy thermosets, along with the degradation of the epoxy thermosets, makes this work attractive for sustainability. This study involved multiple reactions and reactants, such as Diphenyl carbonate (cas: 102-09-0Formula: C13H10O3).

Diphenyl carbonate (cas: 102-09-0) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.Formula: C13H10O3

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Production of aryl oxygen-containing compounds via catalytic pyrolysis of bagasse lignin over La_0.8M_0.2FeO₃ (M=La, Ca, Sr, Ba) was written by Wang, Haiying;Han, Hongjing;Sun, Enhao;Zhang, Yanan;Li, Jinxin;Chen, Yanguang;Song, Hua;Zhao, Hongzhi;Kang, Yue. And the article was included in Journal of Analytical and Applied Pyrolysis in 2019.Recommanded Product: 763-69-9 The following contents are mentioned in the article:

A new method named the production of aryl oxygen-containing compounds via catalytic pyrolysis of bagasse lignin (BL) over perovskites, La_0.8M_0.2FeO₃ (M = La, Ca, Sr, Ba) was proposed. La_0.8M_0.2FeO₃ (M = La, Ca, Sr, Ba) samples were synthesized by the sol-gel method (SG) and characterized by XRD, SEM, BET and XPS, and their catalytic pyrolysis performances were evaluated by the test of TG and the evaluation of the fixed bed microreactor. Under the action of perovskites, the pyrolysis of BL was promoted, the yields of gaseous and solid products decreased while the yield of liquid products increased by 10-20%; decarboxylation and decarbonylation could be inhibited, and it was conducive to the fracture of aliphatic hydrocarbon side chains on aromatic rings, as a result, the selectivity of CO₂/CO decreased while the selectivity of hydrocarbons in gaseous products increased; the total selectivity of aryl oxygen-containing compounds increased from 56 weight% in the liquid product obtained from pure BL pyrolysis to more than 69 weight% in that of catalytic pyrolysis of BL. The spent catalyst was regenerated after controlled combustion of solid product-char, and it showed good structural and catalytic stabilities after 5 successful redox cycles. This study involved multiple reactions and reactants, such as Ethyl 3-ethoxypropanoate (cas: 763-69-9Recommanded Product: 763-69-9).

Ethyl 3-ethoxypropanoate (cas: 763-69-9) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Recommanded Product: 763-69-9

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Use of sequentially inoculation of Saccharomyces cerevisiae and Hanseniaspora uvarum strains isolated from honey by-products to improve and stabilize the quality of mead produced in Sicily was written by Prestianni, Rosario;Matraxia, Michele;Naselli, Vincenzo;Pirrone, Antonino;Badalamenti, Natale;Ingrassia, Marzia;Gaglio, Raimondo;Settanni, Luca;Columba, Pietro;Maggio, Antonella;Bruno, Maurizio;Francesca, Nicola;Moschetti, Giancarlo;Alfonzo, Antonio. And the article was included in Food Microbiology in 2022.Electric Literature of C10H20O2 The following contents are mentioned in the article:

Mead is a beverage produced by alc. fermentation of honey-must. The starter yeasts that are commonly used for the alc. fermentation of honey-must are oenol. Saccharomyces cerevisiae strains. The objective of the present work was, for the first time, to apply yeasts of honey byproducts origin to evaluate the influences the taste-olfactory attributes of mead. For this purpose, three exptl. productions were set up, which included: (i) single inoculation of S. cerevisiae; (ii) single inoculation of Hanseniaspora uvarum; (iii) sequential inoculation of H. uvarum/S. cerevisiae. Two control trials were performed, using a com. strain of S. cerevisiae of oenol. origin and a spontaneous fermentation The results of the chem. parameters showed differences between the trials in terms of residual sugars, acetic acid, glycerol, ethanol and volatile organic compounds Sensorial anal. also showed a high heterogeneity among trials. The attributes of sweetness, honey and floral were found in mead fermented with H. uvarum, whereas all meads obtained with S. cerevisiae were dry, balanced and without off-odors and off-flavours. The results obtained showed that the controlled application of conventional and non-conventional yeast strains isolated from honey byproducts origin could be a promising approach to improve the quality of meads. This study involved multiple reactions and reactants, such as Octyl acetate (cas: 112-14-1Electric Literature of C10H20O2).

Octyl acetate (cas: 112-14-1) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Electric Literature of C10H20O2

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Use of sequentially inoculation of Saccharomyces cerevisiae and Hanseniaspora uvarum strains isolated from honey by-products to improve and stabilize the quality of mead produced in Sicily was written by Prestianni, Rosario;Matraxia, Michele;Naselli, Vincenzo;Pirrone, Antonino;Badalamenti, Natale;Ingrassia, Marzia;Gaglio, Raimondo;Settanni, Luca;Columba, Pietro;Maggio, Antonella;Bruno, Maurizio;Francesca, Nicola;Moschetti, Giancarlo;Alfonzo, Antonio. And the article was included in Food Microbiology in 2022.Reference of 2198-61-0 The following contents are mentioned in the article:

Mead is a beverage produced by alc. fermentation of honey-must. The starter yeasts that are commonly used for the alc. fermentation of honey-must are oenol. Saccharomyces cerevisiae strains. The objective of the present work was, for the first time, to apply yeasts of honey byproducts origin to evaluate the influences the taste-olfactory attributes of mead. For this purpose, three exptl. productions were set up, which included: (i) single inoculation of S. cerevisiae; (ii) single inoculation of Hanseniaspora uvarum; (iii) sequential inoculation of H. uvarum/S. cerevisiae. Two control trials were performed, using a com. strain of S. cerevisiae of oenol. origin and a spontaneous fermentation The results of the chem. parameters showed differences between the trials in terms of residual sugars, acetic acid, glycerol, ethanol and volatile organic compounds Sensorial anal. also showed a high heterogeneity among trials. The attributes of sweetness, honey and floral were found in mead fermented with H. uvarum, whereas all meads obtained with S. cerevisiae were dry, balanced and without off-odors and off-flavours. The results obtained showed that the controlled application of conventional and non-conventional yeast strains isolated from honey byproducts origin could be a promising approach to improve the quality of meads. This study involved multiple reactions and reactants, such as Isopentyl hexanoate (cas: 2198-61-0Reference of 2198-61-0).

Isopentyl hexanoate (cas: 2198-61-0) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits. Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials.Reference of 2198-61-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Selective Synthesis of Non-Aromatic Five-Membered Sulfur Heterocycles from Alkynes by using a Proton Acid/N-Chlorophthalimide System was written by Yu, Wentao;Zhu, Baiyao;Shi, Fuxing;Zhou, Peiqi;Wu, Wanqing;Jiang, Huanfeng. And the article was included in Angewandte Chemie, International Edition in 2021.Reference of 2253-73-8 The following contents are mentioned in the article:

A multicomponent strategy to achieve two different regioselectivities from alkynes, isothiocyanates and H₂O with a proton acid/N-chlorophthalimide (NCPI) system is described to selectively obtain non-aromatic five-membered sulfur heterocycles (1,3-oxathiol-2-imines/thiazol-2(3H)-one derivatives) through multiple bond formations. The process features readily available starting materials, mild reaction conditions, broad substrate scope, good functional-group tolerance, high regio- and chemoselectivities, gram-scale synthesis and late-stage modifications. Mechanistic studies support the proposal that the transformation process includes a combination of H₂O and isothiocyanate, free-radical formation, carbonation and intramol. cyclization to give the products. Furthermore, the 1,3-oxathiol-2-imine derivatives possess unique fluorescence characteristics and can be used as Pd²⁺ sensors with a “turn-off” response, demonstrating potential applications in environmental and biol. fields. Thus, e.g., PhCCPh + EtN:C:S + H₂O → I (84%, 82% isolated, Z/E = 8.5:1) in presence of Fe₂(SO₄)₃.xH₂O, NCPI and HOTf in PhF whereas treatment with NCPI and HCOOH in MeNO₂/HFIP afforded II (61%, 58% isolated). This study involved multiple reactions and reactants, such as Isopropylisothiocyanate (cas: 2253-73-8Reference of 2253-73-8).

Isopropylisothiocyanate (cas: 2253-73-8) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials.Reference of 2253-73-8

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Selective Synthesis of Non-Aromatic Five-Membered Sulfur Heterocycles from Alkynes by using a Proton Acid/N-Chlorophthalimide System was written by Yu, Wentao;Zhu, Baiyao;Shi, Fuxing;Zhou, Peiqi;Wu, Wanqing;Jiang, Huanfeng. And the article was included in Angewandte Chemie, International Edition in 2021.Application In Synthesis of Isopropylisothiocyanate The following contents are mentioned in the article:

A multicomponent strategy to achieve two different regioselectivities from alkynes, isothiocyanates and H₂O with a proton acid/N-chlorophthalimide (NCPI) system is described to selectively obtain non-aromatic five-membered sulfur heterocycles (1,3-oxathiol-2-imines/thiazol-2(3H)-one derivatives) through multiple bond formations. The process features readily available starting materials, mild reaction conditions, broad substrate scope, good functional-group tolerance, high regio- and chemoselectivities, gram-scale synthesis and late-stage modifications. Mechanistic studies support the proposal that the transformation process includes a combination of H₂O and isothiocyanate, free-radical formation, carbonation and intramol. cyclization to give the products. Furthermore, the 1,3-oxathiol-2-imine derivatives possess unique fluorescence characteristics and can be used as Pd²⁺ sensors with a “turn-off” response, demonstrating potential applications in environmental and biol. fields. Thus, e.g., PhCCPh + EtN:C:S + H₂O → I (84%, 82% isolated, Z/E = 8.5:1) in presence of Fe₂(SO₄)₃.xH₂O, NCPI and HOTf in PhF whereas treatment with NCPI and HCOOH in MeNO₂/HFIP afforded II (61%, 58% isolated). This study involved multiple reactions and reactants, such as Isopropylisothiocyanate (cas: 2253-73-8Application In Synthesis of Isopropylisothiocyanate).

Isopropylisothiocyanate (cas: 2253-73-8) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Esters are more polar than ethers but less polar than alcohols. They participate in hydrogen bonds as hydrogen-bond acceptors, but cannot act as hydrogen-bond donors, unlike their parent alcohols. This ability to participate in hydrogen bonding confers some water-solubility.Application In Synthesis of Isopropylisothiocyanate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics